AC won't blow!!!!

My AC won't come through the vents at all. When I put the control on 60 degrees, warm air comes out neer my feet and the vents on top of the dash. I believe the system is fully charged, how can i jump the system? What might be wrong. all fuses are cool.

Re: AC won't blow!!!!

Dont know what year and type of Cad you have, as a guess, I would remove the glove box liner and locate the white plastic arm with the treaded rod snapped into it. Change the temp display from 60 to 90 degrees and watch the arm. It should move the blend door from closed to open. Is the a/c compressor engaged in auto mode? If the arm doesnt move then you have an electrical problem. If the compressor is not engaged you can by pass the low pressure switch on the accumulator with a paper clip or something similar to see if voltage is at the switch. If the compressor engages, then its ususlly a freon amount problem. When you post a concern, please supply all the info about your car so someone can help answer correctly.

Re: AC won't blow!!!!

I had the same problem. I fiddled around trying to interpret the codes but knucked under and took it to a local Unocal garage. The lead mechanic told me here in AZ this is a typical problem with Cadillac's. As rubber does not last very long. He estimated the repair to cost $950 dollars. This included the replecing theprogammer and the mixing box, the one below the glove compartment. BUT, he said if I don't need heat, and believe me no one here ever does, he could bypass those two components and I would have A/C only, for a cost of $23 bucks plus the $70 dianostic. I agreed and it works fine, I just don't have button control to set a desired temp. I am happy, at least for now cause I was starting to sweat more than a runway model on Jeopardy.

In addition: there are two lacal gas stations that will install my parts with only a labor charge. The local Caddy dealers are very very good but I can not afford the there expertise.

Re: AC won't blow!!!!

Hi, it's me again. I should add that I had the same exact problem. Air from the defrost vent and warm air from under the dash vent. Now with the bypass mentioned previously I have vent air and rear center vent air.
For a while I thought I was going, well, KNUTZ. :drinker

Re: AC won't blow!!!!

Originally Posted by lilredrooster

My AC won't come through the vents at all. When I put the control on 60 degrees, warm air comes out neer my feet and the vents on top of the dash. I believe the system is fully charged, how can i jump the system? What might be wrong. all fuses are cool.

Two separate problems. The air temp control is done by the air mix door. Take out the glove box liner as described and you should be able to see the link from the controller to the air mix door that adusts the air flow thru the heater core or the evaporator for cooling. You can disconnect it , as described, and stick it in the "cold" position if the programmer is dead.....

There is a vacuum operated diaphragm that moves the air delivery door from the center vents to the lower and defroster vents. Sounds like that is disconnected or there is no vacuum to it from the engine compartment. Find the vacuum hose underhood that goes to the firewall and HVAC system and make sure that it is connected and that vacuum is getting to the HVAC system. There is a vacuum reservoir bottle and check valve that may be failed/disconnected to hold vac in the system for low vacuum periods so the HVAC still works.

Regarding air temp....is the Ac compressor running and/or are the AC pipes under hood coming from the HVAC case on the firewall cold?? If not , then the air delivery temp issue is more likely due to no AC compressor...not the air mix door. The Ac compressor has to be running for the system to blow cool air.

Re: AC won't blow!!!!

this is a 91 deville with a 4.9l. when i put the control at 60 degrees and cut on the ac nothing happens inside the car at all. just noticed coolant inside the car today, guess my heater core has gone bad.

Re: AC won't blow!!!!

Originally Posted by lilredrooster

this is a 91 deville with a 4.9l. when i put the control at 60 degrees and cut on the ac nothing happens inside the car at all. just noticed coolant inside the car today, guess my heater core has gone bad.

did you check the onboard diagnostics system for any AC codes?? Simultaneously press and hold the OFF and WARMER buttons with the key on until the system activates and then read off the codes.

Does the AC compressor clutch activate when the HVAC control is placed in AUTO??

Why do you think that the system is charged..?? Has it been evacuated and recharged or checked otherwise. At this point in time (13 years old) the system is likely to at least need a top off charge to keep it full and operational. That is an R12 system so it has to be charged with R12.

Re: AC won't blow!!!!

I have a 2003 escalade ext that very very weakly sends out the correct air temp from the correct locations, but, I have no control over volume/speed of the air being sent out. Is there a door/blower/sensor you would suggest I start my quest for a solution with?